1. Field of Invention
The present invention relates to a method and an apparatus for detecting misfire of an engine for a vehicle. More particularly, the present invention relates to a method and an apparatus of detecting precisely whether each of engine cylinders has a misfire or not when the engine cylinders have continuous misfires.
2. Description of Related Art
Generally, power loss, increase of fuel consumption, and vibration of an engine occur when a misfire occurs in the engine of a vehicle instead of normal combustion. The engine has a problem with not only power loss but also overall damage because unburned combustion gas causes a post-explosion in the exhaust manifold. Moreover, environmental pollution is increased because a lot harmful exhaust gas is produced.
In order to prevent this phenomenon, a method of detecting misfire of the engine that detects a cylinder of the engine and restores the engine when misfire occurs in the engine has been studied. A traditional method and an apparatus calculate an angular speed of a crankshaft corresponding to the cylinder of the engine and detect misfire of the engine according to a variation amount or a variation rate of the angular speed.
The traditional method and apparatus can only detect misfire of one or two engine cylinders, such that it cannot detect misfire of three or more engine cylinders.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.